Modular disconnecting drive module with torque vectoring augmentation

ABSTRACT

A drive module having a housing, an input pinion, a ring gear driven by the input pinion, a ring gear bearing supporting the ring gear for rotation relative to the housing, a pair of output shafts and a clutch that selectively transmits rotary power between the ring gear and the output shafts. The clutch includes a clutch input, which is rotatably coupled to the ring gear, a clutch plate separator that is rotatably coupled to the clutch input, a pair of clutch outputs, which are each coupled to a respective one of the output shafts, a pair of clutch packs, which transmit rotary power between the clutch input and a respective one of the clutch outputs, and a pair of apply pistons. The apply pistons are housed in the clutch plate separator.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. application Ser. No.16/122,973 (now U.S. Pat. No. 10,704,663, which issued on Jul. 7, 2020),the disclosure of which is incorporated by reference as if fully setforth in detail herein.

FIELD

The present disclosure relates to a modular disconnecting drive modulewith torque vectoring augmentation.

BACKGROUND

This section provides background information related to the presentdisclosure which is not necessarily prior art.

U.S. Pat. Nos. 6,041,904, 6,098,770 and 6,854,571 are examples of drivemodules that employ a pair of friction clutches instead of a geareddifferential mechanism for supplying propulsive power to a pair ofvehicle wheels. Such configurations can be advantageous, for example,when the drive module is to be provided with torque vectoringcapabilities. While such drive modules are suited for their intendedpurpose, there remains a need in the art for an improved drive module.

SUMMARY

This section provides a general summary of the disclosure, and is not acomprehensive disclosure of its full scope or all of its features.

In one form, the present disclosure provides a drive module thatincludes a housing, an input pinion, a ring gear, a ring gear bearing, aclutch and first and second output shafts. The housing defines a centralcavity, an input axis and an output axis that is transverse to the inputaxis. The input pinion is received in the central cavity and isrotatable about the input axis. The ring gear is received in the centralcavity and is meshed with the input pinion. The ring gear bearing ismounted to the ring gear and the housing. The ring gear bearing supportsthe ring gear for rotation relative to the housing about the outputaxis. The clutch is received in the central cavity and includes a clutchinput, which is coupled to the ring gear for rotation therewith, firstand second clutch outputs, which are rotatable about the output axis, aclutch pack separator, which is disposed along the output axis betweenthe first and second clutch outputs, first and second clutch packs, andfirst and second apply pistons. The clutch pack separator is coupled tothe clutch input for rotation therewith, the first clutch pack havingfirst and second clutch plates that are interleaved together. The firstclutch plates are non-rotatably but axially slidably coupled to theclutch input. The second clutch plates are non-rotatably but axiallyslidably coupled to the first clutch output. The second clutch pack hasthird and fourth clutch plates that are interleaved together. The thirdclutch plates are non-rotatably but axially slidably coupled to theclutch input. The fourth clutch plates are non-rotatably but axiallyslidably coupled to the second clutch output. The first apply piston isdisposed axially between the clutch plate separator and the first clutchpack. The second apply piston is disposed axially between the clutchplate separator and the second clutch pack. The first output shaft iscoupled to the first clutch output for rotation therewith about theoutput axis. The second output shaft is coupled to the second clutchoutput for rotation therewith about the output axis.

In another form, the present disclosure provides a drive module thatincludes a housing, an input pinion, a ring gear, a clutch, a firstoutput shaft, a second output shaft, first and second seals, and thirdand fourth seals. The housing defines a central cavity, an input axisand an output axis that is transverse to the input axis. The inputpinion is received in the central cavity and is rotatable about theinput axis. The clutch received in the central cavity and has a clutchinput, which is coupled to the ring gear for rotation therewith, firstand second clutch outputs, which are rotatable about the output axis, aclutch pack separator, which is disposed along the output axis betweenthe first and second clutch outputs, first and second clutch packs, andfirst and second apply pistons. The clutch pack separator is coupled tothe clutch input for rotation therewith. The first clutch pack has firstand second clutch plates that are interleaved together. The first clutchplates are non-rotatably but axially slidably coupled to the clutchinput. The second clutch plates are non-rotatably but axially slidablycoupled to the first clutch output. The second clutch pack has third andfourth clutch plates that are interleaved together. The third clutchplates are non-rotatably but axially slidably coupled to the clutchinput. The fourth clutch plates are non-rotatably but axially slidablycoupled to the second clutch output. The first apply piston is disposedaxially between the clutch plate separator and the first clutch pack.The second apply piston is disposed axially between the clutch plateseparator and the second clutch pack. The first output shaft is coupledto one of the first and second clutch outputs for rotation therewithabout the output axis. The first output shaft has at least one fluidpassage that extend through at least a portion of the first output shaftin direction parallel the output axis. The first output shaft has afirst fluid outlet, which is coupled to one of the at least one fluidpassage, and a second fluid outlet, which is coupled to one of the atleast one fluid passage. The first and second fluid outlets are spacedapart from one another along the output axis. The second output shaft iscoupled to the other one of the first and second clutch outputs forrotation therewith about the output axis. The clutch plate separatorincludes a hollow hub that is disposed concentrically about a portion ofthe first output shaft. A first supply aperture is formed radiallythrough the hub. The first supply aperture is fluidly coupled to a firstchamber that is disposed between the clutch plate separator and thefirst apply piston. The first and second seals cooperate to seal betweenthe hollow hub and the first output shaft and to fluidly couple thefirst fluid outlet to the first supply aperture. A second supplyaperture is formed radially though the hub. The second supply apertureis fluidly coupled to a second chamber that is disposed between theclutch plate separator and the second apply piston. The third and fourthseals cooperate to seal between the hollow hub and the first outputshaft and to fluidly couple the second fluid outlet to the second supplyaperture. The second and third seals are spaced apart along the outputaxis and are disposed along the output axis between the first and secondfluid outlets.

In yet another form, the present disclosure provides a drive module thatincludes a housing, an input pinion, a ring gear, a clutch, a bearing, afirst output shaft and a second output shaft. The housing defines acentral cavity, an input axis and an output axis that is transverse tothe input axis. The input pinion is received in the central cavity andis rotatable about the input axis. The ring gear is received in thecentral cavity and is meshed with the input pinion. The ring gear has aplurality of teeth and a toe. The toe is located at a radially inner endof the teeth. The clutch is received in the central cavity and has aclutch input, which is coupled to the ring gear for rotation therewith,first and second clutch outputs, which are rotatable about the outputaxis, a clutch pack separator, which is disposed along the output axisbetween the first and second clutch outputs, and first and second clutchpacks. The clutch pack separator is disposed along the output axisbetween the first and second clutch packs and is coupled to the clutchinput for rotation therewith. The first clutch pack has first and secondclutch plates that are interleaved together. The first clutch plates arenon-rotatably but axially slidably coupled to the clutch input. Thesecond clutch plates are non-rotatably but axially slidably coupled tothe first clutch output. The second clutch pack has third and fourthclutch plates that are interleaved together. The third clutch plates arenon-rotatably but axially slidably coupled to the clutch input. Thefourth clutch plates are non-rotatably but axially slidably coupled tothe second clutch output. The bearing supports both the ring gear andthe clutch input relative to the housing for rotation about the outputaxis relative to the housing. The first output shaft is coupled to thefirst clutch output for rotation therewith about the output axis. Thesecond output shaft coupled to the second clutch output for rotationtherewith about the output axis. An outer diameter of the first clutchpack and an outer diameter of the second clutch pack are larger than adiameter of the toe of the ring gear. An inner diameter of the firstclutch pack and an inner diameter of the second clutch pack are smallerin diameter than an outer bearing race of the ring gear bearing.

Further areas of applicability will become apparent from the descriptionprovided herein. The description and specific examples in this summaryare intended for purposes of illustration only and are not intended tolimit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustrative purposes only ofselected embodiments and not all possible implementations, and are notintended to limit the scope of the present disclosure.

FIG. 1 is a perspective view of an exemplary drive module constructed inaccordance with the teachings of the present disclosure;

FIG. 2 is a sectional view of the drive module of FIG. 1 taken along theline 2-2 of FIG. 1;

FIG. 3 is a sectional view taken along the line 3-3 of FIG. 1;

FIG. 4 is an enlarged portion of FIG. 3, illustrating a clutch in moredetail;

FIG. 5 is an enlarged portion of FIG. 3, illustrating the clutch, afirst output shaft, and a stem of a distribution block in more detail;

FIG. 6 is a perspective view of a portion of the drive module of FIG. 1,the view depicting a cover of a hydraulic supply in a partly fragmentedmanner to permit a reservoir inside the cover to be shown;

FIG. 7 is a section view of a portion of the drive module of FIG. 1, theview illustrating a pump and first and second control valves of thehydraulic supply;

FIG. 8 is a perspective view of a portion of the hydraulic supply, theview illustrating a distribution block;

FIG. 9 is a bottom plan view of a portion of the drive module of FIG. 1illustrating the distribution block of the hydraulic supply in moredetail;

FIG. 10 is a perspective view of a portion of the drive module of FIG. 1illustrating the distribution block of the hydraulic supply in moredetail;

FIG. 11 is a sectional view similar to that of FIG. 3 but depictinganother exemplary drive module constructed in accordance with theteachings of the present disclosure; and

FIG. 12 is an enlarged portion of FIG. 11 depicting an additional a sealand reservoir integrated between the first output shaft and the clutchplate separator.

Corresponding reference numerals indicate corresponding parts throughoutthe several views of the drawings.

DETAILED DESCRIPTION

With reference to FIGS. 1 through 3, a drive module constructed inaccordance with the teachings of the present disclosure is generallyindicated by reference numeral 10. The drive module 10 can include ahousing 12, an input pinion 14, a ring gear 16, a ring gear bearing 18,a clutch 20 and first and second output shafts 22 and 24, respectively,a hydraulic supply 26 and a controller 28.

The housing 12 can define a central cavity 36, an input axis 38 and anoutput axis 40 that is transverse to the input axis 38. The housing 12can have first and second housing members 42 and 44 that are axiallyseparable from one another along the output axis 40. The first housingmember 42 can define an input pinion cavity 46, which can be disposedabout the input axis 38 and intersect the central cavity 36, an annularshoulder 48, which is disposed concentrically about the output axis 40,a first coupling portion 50, a distribution block flange 52, and a stemreceiving cavity 54. The first coupling portion 50 can include a pilotbore 60, which can be cylindrically shaped and disposed concentricallyabout the output axis 40, and a first flange member 62 that can bedisposed about the pilot bore 60. The first flange member 62 includes aplurality of threaded apertures (not specifically shown). Thedistribution block flange 52 can be a flat planar surface that is formedonto the first housing member 42 about the stem receiving cavity 54. Thestem receiving cavity 54 can be formed through the distribution blockflange 52 and can intersect the central cavity 36. The second housingmember 44 can define a second coupling portion 64 that can matinglyengage the first coupling portion 50. In the example provided, thesecond coupling portion 64 include a pilot member 66, which can bereceived into the pilot bore 60 in a desired manner (e.g., slip fit orline-to-line fit), and a second flange member 68 that can be fixedlycoupled via bolts (not shown) that are received through the secondflange member 68 and threaded to the threaded apertures in the firstflange member 62. A seal (not specifically shown) can be disposedbetween the first and second coupling portions 50 and 64.

The input pinion 14 can be disposed in the central cavity 36 and canextend through the input pinion cavity 46. The input pinion 14 can besupported by one or more pinion bearings for rotation about the inputaxis 38. In the example provided, the input pinion 14 is supported forrotation via a bearing 70, such as a four-point angular contact bearing,that is configured to transmit thrust loads between the housing 12 andthe input pinion 14 in both axial directions along the input axis 38.The input pinion 14 can be further supported relative to the housing 12via a straddle bearing 72, which can be a roller bearing or a ballbearing. The straddle bearing 72 has radial load capabilities and no orlimited (relative to the four-point angular contact bearing 70)capability to handle thrust loads between the housing 12 and the inputpinion 14. In the example provided, the inner bearing race 70 a of thefour-point angular contact bearing 70 is integrally and unitarily formedwith the input pinion 14.

The ring gear 16 is received in the central cavity 36 and is meshinglyengaged with the input pinion 14 so as to be rotatable about the outputaxis 40. In the example provided, the input pinion 14 and the ring gear16 are hypoid gears, but it will be appreciated that they could beconfigured differently.

The ring gear bearing 18 is mounted to the ring gear 16 and the shoulder48 on the first housing member 42 and supports the ring gear 16 forrotation relative to the housing 12 about the output axis 40. The ringgear bearing 18 is configured to transmit thrust loads between thehousing 12 and the ring gear 16 in both axial directions along theoutput axis 40. In the particular example provided, the ring gearbearing 18 is a four point angular contact bearing having an inner race18 a, which is mounted to the shoulder 48 formed on the first housingmember 42, and an outer race 18 b that is integrally and unitarilyformed with the ring gear 16.

With reference to FIG. 4, the clutch 20 is received in the centralcavity 36 and includes a clutch input 80, first and second clutchoutputs 82 and 84, respectively, a clutch pack separator 86, first andsecond clutch packs 88 and 90, respectively, and first and second applypistons 92 and 94, respectively. The clutch input 80 is coupled to thering gear 16 for rotation therewith. In the example provided, the clutchinput 80 is an outer clutch basket having an annular wall member 96 thatdefines a set of spline teeth 98 that are disposed about the insidecircumferential surface of the annular wall member 96.

The first and second clutch outputs 82 and 84 are spaced apart from oneanother along the output axis 40 and are rotatable relative to oneanother as well as the clutch input 80 about the output axis 40. Each ofthe first and second clutch outputs 82 and 84 includes a hub portion100, which can define an internally-splined aperture 102, and an innerplate mount 104 that can be a sleeve-like structure that can extend fromthe hub portion 100 and which can include a plurality of externalsplines 106 that can be disposed about the circumference of the innerplate mount 104.

The clutch pack separator 86 can include an annular outer wall 110, ahollow hub 112 and a radial wall 114 that extends radially between theouter wall 110 and the hub 112. The outer wall 110 can define aplurality of spline teeth 116 (only one shown) that can non-rotatablybut axially slidably engage with the spine teeth 98 on the annular wallmember 96 of the clutch input 80. Accordingly, it will be appreciatedthat the clutch pack separator 86 is rotatably coupled to the clutchinput 80. The hub 112 can be disposed concentrically within the outerwall 110 and defines a hub aperture 120. The radial wall 114 divides theclutch pack separator 86 into first and second annular chambers 122 and124, respectively, that are disposed on opposite sides of the radialwall 114. First and second supply apertures 126 and 128 can be formedthrough the hub 112 on opposite sides of the radial wall 114.

The first clutch pack 88 has first and second clutch plates 130 and 132,respectively, that are interleaved together. The first clutch plates 130have an externally splined circumference that is matingly received intothe annular wall member 96 of the clutch input 80 so that the externallysplined circumference of the first clutch plates 130 non-rotatably butaxially slidably engage the spline teeth 98 of the clutch input 80. Thesecond clutch plates 132 have an internally splined aperture thatmatingly receives the external splines 106 on the outside circumferenceof the inner plate mount 104 to thereby non-rotatably but axiallyslidably couple the second clutch plates 132 to the first clutch output82.

The second clutch pack 90 has third and fourth clutch plates 134 and136, respectively, that are interleaved together. The third clutchplates 134 have an externally splined circumference that is matinglyreceived into the annular wall member 96 of the clutch input 80 so thatthe externally splined circumference of the third clutch plates 134non-rotatably but axially slidably engage the spline teeth 98 of theclutch input 80. The fourth clutch plates 136 have an internally splinedaperture that matingly receives the external splines 106 on the outsidecircumference of the inner plate mount 104 to thereby non-rotatably butaxially slidably couple the fourth clutch plates 136 to the secondclutch output 84.

The first apply piston 92 can be disposed within the first annularchamber 122 axially between the clutch pack separator 86 and the firstclutch pack 88. The first apply piston 92 can comprise an annular pistonbody 140, an outer peripheral seal 142, which can seal the piston body140 to inside surface 144 of the outer wall 110 of the clutch packseparator 86, and an inner peripheral seal 148 that can seal the pistonbody 140 to the outside surface 150 of the hub 112 of the clutch packseparator 86. The piston body 140 can include a radially outer edge 152,a radially inner edge 154, an annular contact member 156, and a stopmember 158. The radially outer edge 152 can be received in the annularouter wall 110 of the clutch pack separator 86, while the radially inneredge 154 can be received over the hollow hub 112 of the clutch packseparator 86. The outer peripheral seal 142 be coupled to (e.g., formedonto) the radially outer edge 152 and can be sealingly engaged to theannular outer wall 110. The inner peripheral seal 148 can be coupled to(e.g., formed onto) the radially inner edge 154 and can be sealinglyengaged to the hub 112. The annular contact member 156 is configured toengage the first clutch pack 88 when fluid pressure drives the pistonbody 140 away from the radial wall 114 of the clutch pack separator 86.The stop member 158 can be disposed radially between the radially outeredge 152 and the radially inner edge 154 and is configured to contactthe radial wall 114 of the clutch pack separator 86 to limit movement ofthe first apply piston 92 in a direction away from the first clutch pack88. A first chamber 160 can be formed between the radial wall 114 of theclutch pack separator 86 and the piston body 140 of the first applypiston 92. The first chamber 160 can be in fluid communication with thefirst supply aperture 126.

A first return spring 162 can be disposed about the hollow hub 112 andcan bias the first apply piston 92 away from the first clutch pack 88.In the example provided, the first return spring 162 comprises aplurality of helical coil compression springs 164 that are disposedconcentrically about the hollow hub 112 between a pair of spring plates166. A first one of the spring plates 166 abuts the piston body 140 ofthe first apply piston 92, while the other one of the spring plates 166abuts an external retaining ring 168 that is mounted to the hollow hub112.

The second apply piston 94 can be disposed within the second annularchamber 124 axially between the clutch pack separator 86 and the secondclutch pack 90. The second apply piston 94 can comprise an annularpiston body 180, an outer peripheral seal 182, which can seal the pistonbody 180 to an inside surface 184 of the outer wall 110 of the clutchpack separator 86, and an inner peripheral seal 188 that can seal thepiston body 180 to the outside surface 190 of the hub 112 of the clutchpack separator 86. The piston body 180 can include a radially outer edge192, a radially inner edge 194, an annular contact member 196, and astop member 198. The radially outer edge 192 can be received in theannular outer wall 110 of the clutch pack separator 86, while theradially inner edge 194 can be received over the hollow hub 112 of theclutch pack separator 86. The outer peripheral seal 182 be coupled to(e.g., formed onto) the radially outer edge 192 and can be sealinglyengaged to the annular outer wall 110. The inner peripheral seal 188 canbe coupled to (e.g., formed onto) the radially inner edge 194 and can besealingly engaged to the hub 112. The annular contact member 196 isconfigured to engage the second clutch pack 90 when fluid pressuredrives the piston body 180 away from the radial wall 114 of the clutchpack separator 86. The stop member 198 can be disposed radially betweenthe radially outer edge 192 and the radially inner edge 194 and isconfigured to contact the radial wall 114 of the clutch pack separator86 to limit movement of the second apply piston 94 in a direction awayfrom the second clutch pack 90. A second chamber 200 can be formedbetween the radial wall 114 of the clutch pack separator 86 and thepiston body 180 of the second apply piston 94. The second chamber 200can be in fluid communication with the second supply aperture 128.

A second return spring 202 can be disposed about the hollow hub 112 andcan bias the second apply piston 94 away from the second clutch pack 90.In the example provided, the second return spring 202 comprises aplurality of helical coil compression springs 204 that are disposedconcentrically about the hollow hub 112 between a pair of spring plates206. A first one of the spring plates 206 abuts the piston body 180 ofthe second apply piston 94, while the other one of the spring plates 206abuts an external retaining ring 208 that is mounted to the hollow hub112.

Returning to FIG. 3, each of the first and second output shafts 22 and24 is configured to transmit rotary power between a respective one ofthe first and second clutch outputs 82 and 84 and an associated vehiclewheel (not shown). In the example provided, the drive module 10 issuspended independently from a pair of wheels (not shown) that aredriven by the drive module 10. As such, each of the first and secondoutput shafts 22 and 24 includes a male splined shaft member 210 isconfigured to drivingly engage a constant velocity joint (not shown) ofa half-shaft (not shown) that transmits rotary power between arespective one of the first and second clutch outputs 82 and 84 and anassociated vehicle wheel.

With reference to FIG. 5, the first output shaft 22 can include a malesplined segment 220 and a fluid distribution portion 222 having a fluiddistribution section 224, a fluid inlet section 226 and a fluid outletsection 228. The male splined segment 220 can be received into theinternally-splined aperture 102 in the hub portion 100 of the firstclutch output 82 to non-rotatably but axially slidably couple the firstoutput shaft 22 to the first clutch output 82.

The fluid distribution section 224 can comprise one of more channels orpassages that extend longitudinally through the first output shaft 22between the fluid inlet section 226 and the fluid outlet section 228. Inthe example provided, the fluid distribution section 224 comprises afirst passage 230 and a second passage 232. The first passage 230 is adistribution conduit that can be defined in part by a longitudinal bore234 that is formed through the first output shaft 22. The second passage232 is a distribution conduit that can be defined in part by a tube 236that is received into the longitudinal bore 234. The tube 236 can have acentral portion 238, which is formed of a first diameter orcross-sectional area, and end sections 240 a and 240 b that are formedof a second diameter or cross-sectional area that is larger than that ofthe central portion 238. Each of the end sections 240 a and 240 b issealingly engaged to the surface of the longitudinal bore 234. The firstpassage 230 extends axially between the end sections 240 a and 240 b ofthe tube, has an annular cross-sectional shape and is disposed radiallybetween the tube 236 and the surface of the longitudinal bore 234. Thesecond passage 232 includes the volume defined by the tube 236 andextends into the longitudinal bore 234 on sides of each of the endsections 240 a and 240 b that are opposite the second passage 232.

The fluid inlet section 226 can be spaced axially apart from the malesplined segment 220 and can include one or more fluid inlets, which canbe coupled in fluid communication with the fluid distribution section224, and optionally one or more seal mounts 244 a, 244 b, and 244 c. Inthe particular example provided, the fluid inlet section 226 includesthree seal mounts 244 a, 244 b and 244 c, a first fluid inlet 246 thatis disposed between the seal mounts 244 a and 244 b, and a second fluidinlet 248 that is disposed between the seal mounts 244 b and 244 c. Thefirst fluid inlet 246 can comprise one or more holes that are formedradially through the first output shaft 22 and which intersect the firstpassage 230. The second fluid inlet 248 can comprise one or more holesthat are formed radially through the first output shaft 22 and whichintersect the second passage 232.

The fluid outlet section 228 can include one or more fluid outlets,which can be coupled in fluid communication with the fluid distributionsection 224, and optionally one or more seal mounts 250 a, 250 b, and250 c. In the particular example provided, the fluid outlet section 228includes three seal mounts 250 a, 250 b and 250 c, a first fluid outlet252 that is disposed between the seal mounts 250 a and 250 b, and asecond fluid outlet 254 that is disposed between the seal mounts 250 band 250 c. The first fluid outlet 252 can comprise one or more holesthat are formed radially through the first output shaft 22 and whichintersect the first passage 230. The first fluid outlet 252 can be influid communication with the first supply aperture 126. The second fluidoutlet 254 can comprise one or more holes that are formed radiallythrough the first output shaft 22 and which intersect the second passage232. The second fluid outlet 254 can be in fluid communication with thesecond supply aperture 128.

Appropriate seals, such as O-rings 260, can be received on each of theseal mounts 244 a, 244 b, 244 c, 250 a, 250 b and 250 c. The O-rings 260on the seal mounts 250 a, 250 b and 250 c can each form a seal betweenthe first output shaft 22 and the inside diametrical surface of the hubaperture 262 in the hub 112 of the clutch pack separator 86. If desired,bearings, such as a pair of needle bearings 266, can be disposed onopposite axial sides of the fluid outlet section 228 and can support thefirst output shaft 22 for rotation within the hub 112 of the clutch packseparator 86.

The second output shaft 24 can be configured in a conventional mannerand can include a male splined segment 270 that can be received withinand meshingly engage the internally-splined aperture 102 of the hubportion 100 of the second clutch output 84 to thereby rotatably couplethe second output shaft 24 to the second clutch output 84. One of thefirst and second output shafts 22 and 24 can include a bearing bore 274and the other one of the first and second output shafts 22 and 24 caninclude a shaft segment 276. An appropriate bearing, such as a needlebearing 278, can be received between the shaft segment 276 and thebearing bore 274. In the particular example provided, the shaft segment276 is formed on the first output shaft 22 and the bearing bore 274 isformed in the second output shaft 24.

With reference to FIGS. 6 and 7, the hydraulic supply 26 can include apump 300, an electric motor 302, a distribution block 304, a cover 306,first and second control valves 308 and 310, respectively. The electricmotor 302 can operate in response to a motor control signal generated bythe controller 28. The pump 300 can be any type of fluid pump, such as agear pump, and can have a pump housing 320 and a pump input member 322.The pump housing 320 can be fixedly coupled to the electric motor 302,while the pump input member 322 can be drivingly coupled to an outputmember 324 of the electric motor 302.

With reference to FIGS. 7 through 10, the distribution block 304 candefine a distribution block structure 350, a motor/pump mount 352, firstand second valve mounts 354 and 356, respectively, first and second feedconduits 358 and 360, respectively, first and second intermediateconduits 362 and 364, respectively. The distribution block structure 350can include a base 370 and a stem 372. The base 370 is configured tosealingly engage (via a gasket that is not specifically shown) thedistribution block flange 52 on the first housing member 42. The base370 can define one or more drain apertures 378 that are disposed withinan area where the base 370 is sealingly engaged to the distributionblock flange 52. The drain apertures 378 can extend through the base370. The stem 372 can be fixedly coupled to and project from a side ofthe base 370 that faces the distribution block flange 52. The stem 372can be disposed within an area where the base 370 is sealingly engagedto the distribution block flange 52 and can define an output shaftaperture 380. The stem 372 is received into the stem receiving cavity 54(FIG. 5) and the first output shaft 22 (FIG. 5) is received through theoutput shaft aperture 380.

The motor/pump mount 352 is configured to receive the pump 300 and isconfigured to fluidly couple a fluid outlet 382 of the pump 300 to thefirst and second feed conduits 358 and 360. The first and second valvemounts 354 and 356 are configured to mechanically couple the first andsecond control valves 308 and 310, respectively to the base 370. In theexample provided, the first valve mount 354 includes a threaded aperturethat is in fluid communication with the first feed conduit 358 and thesecond valve mount 356 includes a threaded aperture that is in fluidcommunication with the second feed conduit 360. Accordingly, the firstfeed conduit 358 extends between the fluid outlet 382 of the pump 300and the first valve mount 354, while the second feed conduit 360 extendsbetween the fluid outlet 382 of the pump 300 and the second valve mount356. The first intermediate conduit 362 can extend from the first valvemount 354 through the base 370 and through the stem 372 where it canintersect the output shaft aperture 380. Similarly, the secondintermediate conduit 364 can extend from the second valve mount 356through the base 370 and through the stem 372 where it can intersect theoutput shaft aperture 380 at a location that is spaced apart from thefirst intermediate conduit 362. In the example provided, the first andsecond intermediate conduits 362 and 364 are partly formed by groovesthat are formed in the distribution block structure 350; a cover plate386 is secured to the distribution block structure 350 to seal the openside of the grooves in the distribution block structure 350.

With reference to FIGS. 5 and 8, the O-rings 260 that are received oneach of the seal mounts 244 a, 244 b, and 244 c can form seals betweenthe first output shaft 22 and a circumferential surface of the outputshaft aperture 380 so that the first intermediate conduit 362 is influid communication with the first fluid inlet 246 and the secondintermediate conduit 364 is in fluid communication with the second fluidinlet 248.

Returning to FIG. 6, the cover 306 can be coupled to the distributionblock 304 on a side of the distribution block 304 opposite thedistribution block flange 52. The cover 306 can define a fluid reservoir390 that can be in fluid communication with a pump inlet 392 (FIG. 10)of the pump 300 and the drain apertures 378 (FIG. 10) in the base 370.If desired, the cover 306 can include a plurality of cooling fins 394,which promote the rejection of heat to the air around the cover 306, anoil drain plug 396, which permits the fluid in the reservoir 390 to bedrained, and a shroud 398 that shields the underside of the first andsecond control valves 308 and 310 from debris that may be kicked upduring operation of the drive module.

With reference to FIGS. 7 and 9, the first and second control valves 308and 310 can be any type of valve for controlling fluid communicationbetween the first and second feed conduits 358 and 360, respectively,and the first and second intermediate conduits 362 and 364,respectively. In the example provided, the first and second controlvalves 308 and 310 are normally closed, solenoid operated valves thatcan be selectively opened to permit pressurized fluid in the first andsecond feed conduits 358 and 360, respectively, to flow into the firstand second intermediate conduits 362 and 364, respectively. The firstand second control valves 308 and 310 can be responsive to first andsecond valve control signals that are generated by the controller 28 andtransmitted to the first and second control valves 308 and 310,respectively.

Returning to FIGS. 1, 3 and 6, a power source (not shown), such as aninternal combustion engine or an electric motor, can provide rotarypower to the input pinion 14 to cause the input pinion 14 to drive thering gear 16 about the output axis 40. The controller 28 can operate theelectric motor 302 to drive the pump 300 such that the pump 300 drawsfluid from the reservoir 390 and supplies pressurized fluid that istransmitted through the first and second feed conduits 358 and 360 (FIG.7) to the first and second control valves 308 and 310, respectively. Itwill be appreciated that fluid drawn from the reservoir 390 into thepump 300 can pass through a filter (not shown).

With reference to FIGS. 1, 4 and 5, the controller 28 can operate thefirst and second control valves 308 and 310 to supply pressurized fluidto the first and second chambers 160 and 200, respectively. In thisregard, pressurized fluid discharged through the first control valve 308is transmitted (in sequence) through the first intermediate conduit 362,out of the distribution block stem 372 into the first fluid inlet 246 inthe fluid inlet section 226 of the first output shaft 22, through thefirst passage 230 and the first fluid outlet 252, out of the firstoutput shaft 22 and through the first supply aperture 126 in the hub112. Similarly, pressurized fluid discharged through the second controlvalve 310 is transmitted (in sequence) through the second intermediateconduit 364, out of the distribution block stem 372 into the secondfluid inlet 248 in the fluid inlet section 226 of the first output shaft22, through the second passage and the second fluid outlet 254, out ofthe first output shaft 22 and through the second supply aperture 128 inthe hub 112. Pressurized fluid in the first and second chambers 160 and200 can urge the first and second apply pistons 92 and 94, respectively,toward the first and second clutch packs 88 and 90, respectively, tothereby compress the first and second clutch packs 88 and 90,respectively. It will be appreciated that the magnitude of the torquethat can be transmitted between the ring gear 16 and each of the firstand second output shafts 22 and 24 is at least partly dependent upon themagnitude of the force exerted by the first and second apply pistons 92and 94, respectively, to the first and second clutch packs 88 and 90,respectively. It will also be appreciated that the first and secondcontrol valves 308 and 310 could be operated differently so that theforces exerted on the first and second clutch packs 88 and 90,respectively, are different. The application of different forces to thefirst and second clutch packs 88 and 90 could be employed, for example,to permit a difference in rotational speed between the first and secondoutput shafts 22 and 24.

If desired, the reduction ratio or speed ratio of the input pinion 14and the ring gear 16 can be selected to drive the clutch input 80 at arotational speed than a desired rotational speed of the first and secondoutput shafts 22 and 24. Accordingly, the controller 28 can operate thefirst and second control valves 308 and 310 such that the force exertedby the first and second apply pistons 92 and 94, respectively, to thefirst and second clutch packs 88 and 90, respectively, permits a desiredamount of relative rotation between the clutch input 80 and the firstand second output shafts 22 and 24, respectively. Stated another way,the controller 28 can operate the first and second control valves 308and 310 to limit the torque that is output from the clutch 20 to thefirst and second output shafts 22 and 24 to drive the first and secondoutput shafts 22 and 24 at a rotational speed that is relatively slowerthan the rotational speed of the clutch input 80. Configuration of thereduction ratio or speed ratio of the input pinion 14 and the ring gear16 in this manner provides a torque-vectoring capability in which anadditional amount of speed and torque can be applied to one of the firstand second output shafts 22 and 24 and a lesser amount of speed andtorque can be applied to the other one of the first and second outputshafts 22 and 24.

In a first alternative, a single one of the first and second controlvalves 308 and 310 could be employed to control the fluid pressure thatacts on the first and second apply pistons 92 and 94, for example if a)the first and second intermediate conduits 362 and 364 (FIG. 9) were tobe coupled in fluid communication, and/or b) the first and second fluidinlets 246 and 248 (FIG. 5) were to be coupled in fluid communication,and/or c) the first and second passages 230 and 232 (FIG. 5) were to becoupled in fluid communication, and/or d) the first and second fluidoutlets 252 and 254 (FIG. 5) were to be coupled in fluid communication,and/or d) the first and second supply apertures 126 and 128 (FIG. 4)were to be coupled in fluid communication, and/or e) the first andsecond chambers 160 and 200 (FIG. 4) were to be coupled in fluidcommunication. In a second alternative, the first and second controlvalves 308 and 310 could be omitted and the electric motor 302 could becontrolled by the controller 28 to control the fluid pressure that actson the first and second apply pistons 92 and 94 (FIG. 4).

With reference to FIG. 11, another exemplary drive module constructed inaccordance with the teachings of the present disclosure is generallyindicated by reference numeral 10 a. The drive module 10 a can begenerally identical to the drive module 10 of FIG. 1, except for thefirst output shaft 22 a, the clutch pack separator 86 a, and the sealingbetween the first output shaft 22 a and the clutch pack separator 86 a.

With reference to FIG. 12, the first output shaft 22 a has first andsecond fluid outlets 252 a and 254 a, a plurality of seal mounts 250-1,250-2, 250-3, 250-4, and a reservoir 410. In contrast to theabove-described embodiment, the first fluid outlet 252 a receivespressurized fluid from the second passage 232 a and is coupled to secondannular chamber 124 (FIG. 11) via the second supply aperture 128 a inthe clutch pack separator 86 a to provide fluid power to the secondapply piston 94 (FIG. 11), while the second fluid outlet 254 a receivespressurized fluid from the first passage 230 a and is coupled to firstannular chamber 122 (FIG. 11) via the first supply aperture 126 a (shownin broken line rotated out of position) in the clutch pack separator 86a to provide fluid power to the first apply piston 92 (FIG. 11). Thefirst supply apertures 126 a are formed in the clutch pack separator 86a in a manner that is similar to that of the second supply apertures 128a, except that the first supply apertures 126 a are disposed 90 degreesapart from the second supply apertures 128 a about the output axis 40.

The seal mounts 250-1 and 250-2 are disposed along the output axis 40such that the first fluid outlet 252 a is disposed axially between theseal mounts 250-1 and 250-2, while the seal mounts 250-3 and 250-4 aredisposed along the output axis 40 such that the second fluid outlet 254a is disposed axially between the seal mounts 250-3 and 250-4. As in theabove-described embodiment, each of the seal mounts 250-1, 250-2, 250-3and 250-4 is sized to receive a seal, such as an O-ring 260, which issealed to the first output shaft 22 a and to the clutch plate separator86 a.

The reservoir 410 can be disposed along the output axis 40 axiallybetween the first and second fluid outlets 252 a and 254 a, and morepreferably between the seal mount associated with the first fluid outlet252 a and the seal mount associated with the second fluid outlet 254 athat are axially closest to one another (i.e., the seal mounts 250-2 and250-3 in the example provided). The reservoir can be an annular groovethat is disposed partly or fully about the circumference of the firstoutput shaft 22 a. Additionally, or alternatively, the reservoir 410could also comprise features that are formed into the insidecircumferential surface of the clutch plate separator 86 a (e.g., anannular groove formed partly or fully about the clutch plate separator86 a).

It will be appreciated that pressurized fluid can be transmitted throughthe second and first passages 232 a and 230 a in the first output shaft22 a and out the first and second fluid outlets 252 a and 254 a,respectively, to feed the second and first annular chambers 124 and 122,respectively, through the second and first supply apertures 128 a and126 a, respectively. Configuration of the seal mounts, seals between thefirst output shaft 22 a and the clutch plate separator 86, and thereservoir 410 provide relatively more reliable operation of the firstand second clutch packs 88 and 90 (FIG. 11) as compared to theembodiment of FIG. 1. In this regard, the provision of pressurized fluidto cause the first and second clutch packs 88 and 90 (FIG. 11) to switchfrom a disengaged state to an engaged state exerts fluid pressure on theO-rings 260, which would normally cause each O-ring 260 to tend to moveor deform in an axial direction along the output axis 40 such that theeach O-ring 260 seals against an internal wall of its associated sealmount that is furthest from the associated one of the fluid outlets inthe first output shaft 22 a. In a situation where a single O-ring 260 isemployed to seal against pressurized fluid discharged from both thefirst and second fluid outlets, each side of the O-ring 260 is subjectedto the same force and as such, the single O-ring 260 is at times notable to sealingly engage both the clutch pack separator and the firstoutput shaft. The provision of a pair of O-rings 260 mounted in a pairof seal mounts 250-2 and 250-3 that are disposed along the output axis40 between the first and second outlets 252 a and 254 a solves thisissue. Moreover, any fluid that may initially leak past one of theO-rings 260 in the seal mounts 250-2 and 250-3 prior to the sealing ofthat O-ring 260 against the inner wall of the associated seal mount canbe received into the reservoir 410. While the reservoir 410 isrelatively small, it is sufficient in volume to prevent the leaked fluidfrom interfering with the sealing of either O-ring 260 in the sealmounts 250-2 and 250-3 (i.e., an O-ring which pressurized fluid hasinitially leaked past and the other one of the O-rings).

The foregoing description of the embodiments has been provided forpurposes of illustration and description. It is not intended to beexhaustive or to limit the disclosure. Individual elements or featuresof a particular embodiment are generally not limited to that particularembodiment, but, where applicable, are interchangeable and can be usedin a selected embodiment, even if not specifically shown or described.The same may also be varied in many ways. Such variations are not to beregarded as a departure from the disclosure, and all such modificationsare intended to be included within the scope of the disclosure.

What is claimed is:
 1. A drive module comprising: a housing defining acentral cavity, an input axis and an output axis that is transverse tothe input axis; an input pinion received in the central cavity androtatable about the input axis; a ring gear received in the centralcavity and meshed with the input pinion, the ring gear having aplurality of teeth and a toe, the toe being located at a radially innerend of the teeth; a clutch received in the central cavity, the clutchhaving a clutch input, which is coupled to the ring gear for rotationtherewith, first and second clutch outputs, which are rotatable aboutthe output axis, a clutch pack separator, which is disposed along theoutput axis between the first and second clutch outputs, and first andsecond clutch packs, the clutch pack separator being disposed along theoutput axis between the first and second clutch packs and being coupledto the clutch input for rotation therewith, the first clutch pack havingfirst and second clutch plates that are interleaved together, the firstclutch plates being non-rotatably but axially slidably coupled to theclutch input, the second clutch plates being non-rotatably but axiallyslidably coupled to the first clutch output, the second clutch packhaving third and fourth clutch plates that are interleaved together, thethird clutch plates being non-rotatably but axially slidably coupled tothe clutch input, the fourth clutch plates being non-rotatably butaxially slidably coupled to the second clutch output; a bearingsupporting both the ring gear and the clutch input relative to thehousing for rotation about the output axis relative to the housing; afirst output shaft coupled to the first clutch output for rotationtherewith about the output axis; and a second output shaft coupled tothe second clutch output for rotation therewith about the output axis;wherein an outer diameter of the first clutch pack and an outer diameterof the second clutch pack are larger than a diameter of the toe of thering gear, and wherein an inner diameter of the first clutch pack and aninner diameter of the second clutch pack are smaller in diameter than anouter bearing race of the ring gear bearing.
 2. The drive module ofclaim 1, further comprising a first apply piston that is configured tomove along the output axis in a direction toward the ring gear tocompress the first clutch pack.
 3. The drive module of claim 2, whereinthe first apply piston is sealingly engaged to the clutch plateseparator.
 4. The drive module of claim 2, further comprising a secondapply piston that is movable along the output axis for compressing thesecond clutch pack.
 5. The drive module of claim 4, wherein the secondapply piston moves along the output axis in a direction away from thering gear to compress the second clutch pack
 6. The drive module ofclaim 5, wherein the second apply piston is sealingly engaged to theclutch plate separator
 7. The drive module of claim 1, wherein thebearing is mounted to the ring gear and the housing.
 8. The drive moduleof claim 7, further comprising a first apply piston that is configuredto move along the output axis in a direction toward the ring gear tocompress the first clutch pack.
 9. The drive module of claim 8, whereinthe first apply piston is sealingly engaged to the clutch plateseparator.
 10. The drive module of claim 8, further comprising a secondapply piston that is movable along the output axis for compressing thesecond clutch pack.
 11. The drive module of claim 10, wherein the secondapply piston moves along the output axis in a direction away from thering gear to compress the second clutch pack
 12. The drive module ofclaim 11, wherein the second apply piston is sealingly engaged to theclutch plate separator.
 13. A drive module comprising: a housingdefining a central cavity, an input axis and an output axis that istransverse to the input axis; an input pinion received in the centralcavity and rotatable about the input axis; a ring gear received in thecentral cavity and meshed with the input pinion; a clutch received inthe central cavity, the clutch having a clutch input, which is coupledto the ring gear for rotation therewith, first and second clutchoutputs, which are rotatable about the output axis, a clutch packseparator, which is disposed along the output axis between the first andsecond clutch outputs, first and second clutch packs, and first andsecond apply pistons, the clutch pack separator being coupled to theclutch input for rotation therewith, the first clutch pack having firstand second clutch plates that are interleaved together, the first clutchplates being non-rotatably but axially slidably coupled to the clutchinput, the second clutch plates being non-rotatably but axially slidablycoupled to the first clutch output, the second clutch pack having thirdand fourth clutch plates that are interleaved together, the third clutchplates being non-rotatably but axially slidably coupled to the clutchinput, the fourth clutch plates being non-rotatably but axially slidablycoupled to the second clutch output, the first apply piston beingdisposed axially between the clutch plate separator and the first clutchpack, the second apply piston being disposed axially between the clutchplate separator and the second clutch pack; a first output shaft coupledto one of the first and second clutch outputs for rotation therewithabout the output axis, the first output shaft having at least one fluidpassage that extend through at least a portion of the first output shaftin direction parallel the output axis, the first output shaft having afirst fluid outlet, which is coupled to one of the at least one fluidpassage, and a second fluid outlet, which is coupled to one of the atleast one fluid passage, the first and second fluid outlets being spacedapart from one another along the output axis; and a second output shaftcoupled to the other one of the first and second clutch outputs forrotation therewith about the output axis; wherein the clutch plateseparator comprises a hollow hub that is disposed concentrically about aportion of the first output shaft, wherein a first supply aperture isformed radially through the hub, the first supply aperture being fluidlycoupled to a first chamber that is disposed between the clutch plateseparator and the first apply piston; wherein first and second sealscooperate to seal between the hollow hub and the first output shaft andto fluidly couple the first fluid outlet to the first supply aperture;wherein a second supply aperture is formed radially though the hub, thesecond supply aperture being fluidly coupled to a second chamber that isdisposed between the clutch plate separator and the second apply piston;wherein third and fourth seals cooperate to seal between the hollow huband the first output shaft and to fluidly couple the second fluid outletto the second supply aperture; wherein the second and third seals arespaced apart along the output axis and are disposed along the outputaxis between the first and second fluid outlets.
 14. The drive module ofclaim 13, wherein the first apply piston is sealingly engaged to theclutch plate separator.
 15. The drive module of claim 14, wherein theclutch plate separator defines an annular chamber in which the firstapply piston is received.
 16. The drive module of claim 14, wherein thesecond apply piston is sealingly engaged to the clutch plate separator.17. The drive module of claim 16, wherein the clutch plate separatordefines first and second annular chambers, the first apply piston beingreceived in the first annular chamber, the second apply piston beingreceived in the second annular chamber.
 18. The drive module of claim13, wherein the housing has first and second housing members that areaxially separable from one another along the output axis.
 19. The drivemodule of claim 13, further comprising a distribution block having abase and a stem that extends from the base, the stem extending into thecentral cavity in the housing and defining a shaft aperture throughwhich the first and output shaft is received through, the stem beingsealingly engaged to the first output shaft and being fluidly coupled tothe at least one fluid passage.
 20. The drive module of claim 19,wherein the distribution block includes a pump mount to which a pump iscoupled, the pump being configured to supply a pressurized fluid to thestem.
 21. The drive module of claim 20, further comprising a firstcontrol valve mounted to the distribution block and disposed in a firstfluid path between the pump and an end of a first intermediate conduitin the stem that intersects the shaft aperture.
 22. The drive module ofclaim 13, wherein the at least one fluid passage comprises first andsecond fluid passages, wherein the first fluid outlet is coupled to thefirst fluid passage, and wherein the second fluid outlet is coupled tothe second fluid passage.
 23. The drive module of claim 13, wherein theat least one fluid passage comprises a single fluid passage to which thefirst and second fluid outlets are coupled.
 24. The drive module ofclaim 13, further comprising a ring gear bearing mounted to the ringgear and the housing, the ring gear bearing supporting the ring gear forrotation relative to the housing about the output axis.